Billiton Limited is listed on the ASX and is expanding its business operations into China. In order to expand, the company will need to raise additional funds through the issue of corporate bonds direct to the capital markets. Two securities that are often issued into the corporate bond market are debentures and unsecured notes. 

a) Discuss the structure and attributes of each of these securities. 

b) Within the context of a bond issued by a corporation, discuss the nature of a fixed and floating charge. 

c) Explain which types of borrowers will have access to funds through the issue of debentures and unsecured notes into the capital markets.